Process of making packages of artificial yarn



Patented Mar. 29, 1938 UNITED STATES PATENT OFFICE of artificial yarn having characteris knot count and a uniform yardage. lowing specification and claims, the or its equivalent, unless otherwise stated, is meant to include only those knots arising from package during various textile transference of the yarn operations.

Generally speaking, the preparation of a celluckage is achieved sting of spinning,

lose acetate yarn shipping in three textile operations consi twisting, and coning.

In the spinning step, generally a filamentous yarn is dry spun in a spinning cell and wound on a bobbin immediately after issuance from the In attempting to obtain a spinning package of a given size, the thread is wound on the collecting means for a given perio uled according to the particular yarn, spinning speed chosen. At the end of this scheduled period, the operators pro ning cells and windup positions composing the spinning machine, and each position is dofied by bobbin for the com- In making spinning packages in this fashion, I have now observed, particularly at high spinning speeds of 300 yards or more per minute, that the yardage in spinning packages containing the varies considerably from packa though spun on the same or cell.

substitution of an empty pleted spinning package.

machines.

This yardage var satisfactorily overcome tion.

I rnoonss 0 F MAKING PACKAGES OF ARTIFICIAL YARN Ernest Lee Griggs, Jr., Waynesboro, Va... assignor to E. I. du Pont de Nemours & Company, Wilmington/Del a corpor ation of Delaware '3 Claims. (01117-21) 45 spinning packages containing from pounds of cellulose acetate yarn is given the desired degree of twist on a downtwister, and is wound on a pirn or like carrier to form a pirn package containing approximately 1 pounds of Generally, the operators patrol back and forth along the length of several downtwister machines composed of a plurality of spindlepositions and, as the yarn from a supply spinruns out, new supply spinning the desired size of 50 twisted yarn.

w ning package 55 packages are tied in until d of time, scheddenier, and

ceed along the spinsame denier yarn ge to package even different spinning iation arises in large part, from such factors and sources as the dofling skill of the individual operators, the spinning speeds of the individual spinning machines, slight departures from the scheduled doifing time, etc. This difflculty of yardage variation in spinning packages of the same denier yarn has never been until my present invenpirn package is secured. When the operators, by visual gauging, judge the pirn packages to be of the desired weight, the spindle position is stopped and the pirn packageis dofied and replaced with an empty pirn. Twistingof the yarn remaining on the supply package on to the empty pirn is immediately started and the process is repeated; a sufficient number of additional spinning packages being tied in to yield the requisite size of pirn package. For convenience, this system is described as staggered supply and staggered dofling.

In the throwing step, the twisted yarn from the pirn package is transferred by a winding operation on to a. lightweight core, such as a paper' cone or metallic spool.

Proceeding in the above-described fashion, one obtains surprisingly frequently in the shipping, package produced by the three operations more knots andmorevarlations in yardage than would naturally be expected. The presence of knots in the yarn is a distinct disadvantage in that the knots interfere with the needles and frequently cause stoppage and expensive delays in weaving, knitting, and like textile operations. The variation in yarn yardage is a source of trouble in that the yarn packages exhaust unevenly and before the completion of the textile operation.

One object of the present invention, therefore, is to furnish shipping packages containing a 30 minimum of knots.

Another object of the invention is to furnish for a given yarn denier shipping packages containing substantially the same yarn yardage.

Another object of the invention is to wind con- 35 sistently at the spinning machine yarn packages containing substantially the same yardage of I a given denier sized or unsized yarn.

Another object of the invention is to employ on downtwister machines-supply spinning pack- 40 ages containing 2 or .more pounds of yarn.

Another objectof the invention is 'to form on downtwister machines pirn packages of knotless twisted yarn. r

Specifically, the object of the invention is to form, during three manufacturing steps, a shipping'package of twisted cellulose acetate yarn containing not morethan one knot.

More specifically, theobject of the invention is tofurnish a process wherein the above objectives are accomplished. I I

According to my invention, a shipping package of celluloseacetate yarn'containing not more than one knot is produced, in three manufacturing operations, bya process comprising contin- 5 ning carrier to produce therefrom at least one pirn package containing a substantially predetermined yarn yardage and winding or throwing the yarn from at least two of the said unit pirn packages upon a lightweight support to form the said shipping package.

In the preferred embodiment of the invention,

' the spinning, twisting, and throwing operations are conducted in the following manner:

In the spinning operation, a meter or other yardage-measuring device is connected to the face drive roll, on which rests the yarn-collecting means of the spinning machine, or, in the case of cap spinning, to the drive roll preceding the cap spinner. In turn, this yardage meter is connected to a clock counter graduated in such a fashion as to designate when each position of the spinning machine should be dofl'ed. The clock counter and meter device is so set that 25,000900,000 yards of continuous filamentous yarn are spun and wound before the clock counter begins to move, the exact yardage setting depending on the yarn denier being spun. The yarn is collected, preferably, ona sleeve bobbin. When the meter indicates that the predetermined requisite yarn yardage hascollected'on the sleeve bobbin at the first position of the spinning machine, the hand of the clock counter moves to the No. 1 position on the graduated scale, and the operator dofls the completed spinning package and starts the continuously spun yarn winding on an empty bobbin sleeve. Thereafter, at definite time intervals, the counter hand moves progressively to Nos. 2, 3, 4, 5,-6, 7, 8, etc. positions on the scale, and the operator in sequence therewith doifs spinning positions Nos. 2, 3, 4, 5, 6,- '7, 8, etc. and simultaneously starts the formation of spinning packages on empty bobbin sleeves. In like manner, the

. entire spinning machine is .doiled and the yarn allowed to collect once more into spinning packages until the meter again indicates that the first spinning position is to be dofl'ed. By operating in this fashion, there is formed a completed spinning package containing 2, 3, or more pounds of knotless yarn and having a yardage variation of as little as 1-2% based on the total yardage of the package.

In the twisting operation, a 2, 3, or more pounds unit spinning package is twisted on a downtwister machine to form two or more unit ,pirn packages containing knotless yarn, and each pim having substantially the same yardage for a given denier yarn.

A yardage-measuring device, such as ameter, is connected on the downtwister machine to the drive roll feeding the yarn to the ring traveler and pim. when the predetermined requisite yardage v .is collected on the pirn as indicated on the meter,

the first spindle position is shut down, the pim package is withdrawn, and an empty pirn is substituted. After shutting down the first spindle position, at definite time intervals of approximately one minute successive spindle positions are shut down until approximately 25% of the spindle positions of the spinning machine arestopped, when the entire machine is shut down. The pim packages on the remaining positions are then doifed and replaced with empty pirns.

After resetting the meter yardage-measuring device, the downtwister machine is started, the empty pirns tied to their individual supply spinning package, and a predetermined yardage of yarn is twistedon to the pirns in the same fashion as in the case of the first set of pirns. By operating in this fashion, the supply spinning packages run out substantially evenly along the entire machine while forming sets of unit pirn packages the doifing of the entire downtwister niachine inthe above fashion is designated as "flat dofling and the term unit package is used to denote the package containing a, predetermined yardage of twisted yarn. It will, of course, be obvious that a knotless package is obtained by the use of a fiat supply and the fiat dofllng of a unit package.

In the coning operation, i. e., in the winding of the yarn into the final, shipping package, the twisted yarn from two or more of the previously prepared unit pirn packages is transferred to a paper cone or similar lightweight core to form the desired sized shipping package containing a weight of yarn which is an even multiple of the weight of yarn in the pirn package.

By operating in the above preferred manner, the number of knots arising from package trans fer in the final shipping package depends entirely on the number of unit pirn packages going into the same. For example, in making a 3-pound cone package from two 1% pound pirn packages there will be only one knot in the final package from package transference during the three steps of spinning, twisting, and throwing. That is to say, the number of knots will be one less than the number of unit pirn packages going into the shipping packages.

While the above represents the preferred proces of the invention, it will be obvious to those skilled in the art that various modifications may be made withoutdeparture from the principles taught by the invention.

The number of yards of yarn wound on the spinning package should at least be 22,000 yards and preferably should be 45,000 to 900,000 yards or more, Naturally, the number of yards in a spinning package of given weight varies with the denier of the yarn being spun. In spinning a low denier yarn, more yards are wound on the spinning package than in spinning a heavy denier yarn. Thus, in spinning a 30 denier yarn, preferably 223,000 to 893,000 yards of yarn are wound into a spinning package, whereas in spinning a 300 denier yarn 22,000 to 90,000 yards are wound into a spinning package. In all cases, however, proceeding according to the process of the invention, spinning packages of a given denier yarn are taining individually substantially the same yarn yardage.

Of course, different downtwister machines are equipped with the above-mentioned knotless supply spinning packages containing at least 22,300 yards and preferably 45,000 to 76 893,000 yards of yarn, provided supply spinning packages of the same yardage are employed on each downtwister machine. At least two pirn packages of twisted yarn are made from each supply spinning package, and in no case is more than one supply spinning package used in making two pirn packages of twisted yarn. Preferably,

one supply spinning package is measured oil in the downtwisting operation to form two to four unit pirn packages of twisted knotless yarn. The pirn packages of twisted knotless yarn contain from 22,300 to M1000 yards of continuous yarn, according to the particular denier being spun. In fiat dofiing on a downtwisting machine, certain minor deviations may be made without losing the advantages of the invention. Thus, in starting the twisting operation, the yarn ends of the supply packages may all be tied to the empty pirns and all the spindle positions of the downtwister started simultaneously; From an operating standpoint, however, this is less advantageous and, since the speed of the twisting machine is relatively slow and there is relatively little time lag between the starting of the first spindle position and the end spindle position by the operator, the error in yarn yardage is relatively small.

It is important in the downtwisting operation that a flat supply and flat dofling system be used in order that unit packages are obtained and in order that the beginning of a supply spinning v package coincides with the beginning of the formation of the pirn package andthe end of the supply package coincides with (the end of the formation of the same or a different pirn package. The result is a unit pirn package containing at least 22,300 yards of knotless twisted yarn.

In the throwing step,'it is preferred that the shipping package be made from .two unit-pirn packages 01 knotless twisted yarn.v The final package, accordingly, will contain preferably at least 45,000 to 893,000 yards or more of twisted 'yarn containing only one knot.

While the above invention is described for convenience in terms of cellulose acetate yarn;

it will be obvious that the process may "advantageously be applied in the manufacture of shipping packages of any continuously dry spun yarn comprised of an organic derivative of cellulose. Thus, instead of cellulose acetate, the yarn may be comprised of organic esters of cellulose such as cellulose acetopropionate, cellulose acetobue tyrate, cellulose acetostearate, or cellulose pro- .pionate, or of cellulose ethers such as ethyl or 1 benzyl cellulose. It may also be applied to artiflcial yarn made from viscose or from cuprammonium cellulose, particularly when made by the bobbin process, or to other types of artificial gm 7 Theputstanding advantage of the invention is that it gives in its preferred form a shipping package containing at the most only one knot during three textile operations and having substantially the same yardage for a given denier yarn. However, the invention also has the advantage of eliminating to a large extent burdensome bookkeeping as to the times at which numerous spinning and twisting machines should be doiled, since such is substantially automatically taken care of by the process of the invention. The process of the invention also ofiers the advantage of automatically pacing the operators in doffing various positions at the spinning machine. The process also eliminates any variation in yardage arising from miscellaneous factors such as difierence in drive'roll speeds, etc. In the twisting operation, the simultaneous completion and removal of supply spinning packages on an entire downtwister machine is of great assistance to the operator. Moreover, in using the fiat dofing'system on the downtwisters, all the spindle positions are down at one time and free of yarn so that the machine may be thoroughly cleaned, if desired, without contaminating and lowering the quality of the yarn. In addition, it is possible to spin large packages on the spinning machine, and to twist into pirn packages which contain an even fraction, e. g.,

/2, $41, etc.of the yardage contained in the spun package, thus permitting the use of pirns sufliciently small to enable accurate control of twisting, elimination of mechanical difliculties, low initial expense and low maintenance costs.

Any modification of the invention which conforms to the spirit thereof, is intended to be included within the scope of the claims.

I claim:

1. In a process for the production of improved, artificial yarn wound packages, the steps which comprise spinning from a liquid thread-forming medium, a number 01. spun'packages of thread containing substantially the same denier and yardage, twisting said packages into twisted "thread packages which contain substantially equal yardage but which is a fraction of the yardage of said spun packages, then winding said twisted thread packages into a number of final thread packages of substantially equal yardage, the yardage in said final packages being substantially an even multiple of the yardage in said twisted thread packages.

2. The process as definedin claim 1, characterized in that the yarn is cellulose ester yarn.

3. The process as defined in claim 1, characterized in that the yarn is cellulose acetate yarn.

ERNEST LEE GRIGGS, JR. 

